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1.
《Molecular therapy》2022,30(5):1885-1896
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ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy.  相似文献   
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Background Context

The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).

Purpose

The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.

Design

We carried out a post hoc analysis of a prospectively collected database in a level I spine center.

Patients Example

The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.

Outcome Measures

Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.

Methods

We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.

Results

The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.

Conclusions

Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection.  相似文献   
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Purpose

To evaluate the feasibility of a same-day yttrium-90 (90Y) radioembolization protocol with resin microspheres (including pretreatment angiography, lung shunt fraction [LSF] determination, and radioembolization) for the treatment of hepatocellular carcinoma (HCC) and liver metastases.

Materials and Methods

All same-day radioembolization procedures performed over 1 y (February 2017 to January 2018) were included in this single-institutional retrospective analysis, in which 34 procedures were performed in 26 patients (median age, 63 y; 13 women), 19 with liver metastases and 7 with HCC. Yttrium-90 treatment activities were calculated by body surface area method. Tumor imaging response was assessed by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 for liver metastases and modified RECIST for HCC. Clinical side effects and adverse events were graded per Common Terminology Criteria for Adverse Events version 4.0.

Results

All planned cases were technically successful, and no cases were canceled for elevated LSF or vascular anatomic reasons. Pretreatment angiography modified the planned 90Y treatment activity in 1 case in which vascular anatomy required a lobar-dose split into 2 for segmental infusions. In 18% of cases, patients were briefly admitted after the procedure for observation or symptom management. Imaging evaluation of initial efficacy at 1 month demonstrated partial response in 25% and stable disease in 67% of patients with liver metastases and partial/complete response in 43% and stable disease in 14% of patients with HCC. Grade ≥ 3 adverse events occurred in 6% of cases, with no systemic therapy–limiting toxicities. The mean total procedure time was 4.2 hours.

Conclusions

A same-day 90Y radioembolization protocol with resin microspheres is feasible in select patients, which can expedite cancer therapy.  相似文献   
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Simulated data using a linear one- and two-compartment body model with different absorption characteristics were used to evaluate the ability of single dose bioavailability data to predict the relationships that exist at steady state. This was done by comparing the confidence intervals obtained from single and multiple dose data sets for the parameters of Tmax, Cmax, and area under the curve from time zero to infinity (AUC0-infinity). As a consequence of Tmax and Cmax decreasing and increasing from single to multiple dosing regimens, the confidence intervals for these parameters reflected these changes. The 90 per cent confidence interval expressed as a percentage of the reference mean increased or decreased for Tmax dependent upon the ratio of Ka test/Ka reference, and decreased for Cmax while the interval for AUC0-infinity exhibited no predictable pattern and appeared to be influenced by the amount of error in the data set. Alteration of either the dosing interval or the fraction absorbed did not affect the pattern of change in the confidence intervals for Tmax and Cmax, but the latter did result in a decrease in the interval for AUC0-infinity. Analysis of the confidence intervals for Tmax, Cmax and AUC0-infinity in bioequivalency studies for quinidine gluconate and procainamide hydrochloride following administration of single and multiple doses to different subjects appeared to be consistent with the patterns observed for the simulated data sets.  相似文献   
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目的:了解温州地区人群不同年龄组骨质疏松患病率及同年龄组男女骨质疏松患病的差异,强调早期预防治疗老年人及绝经期妇女骨质疏松的重要性,方法:应用单能量X线(SXA)骨密度仪测量246例正常人的右跟骨骨密度,结果:男性大于60岁组较小于60岁组骨密度(BMD)降低明显(P<0.05);女性50岁以上组与小于50岁组相比,BMD下降差异有极显性(P<0.01);各年龄组男女相比,男性BMD明显高于女性(P<0.05)。结论:女性骨质疏松症的发病大多以绝经后为主,雌激素在维持骨量方面具有重要的作用。SXA检测的跟骨含95%小梁骨,能较好地确定骨质疏松的风险水平,且其具有价廉、简便,快捷,较准确等特点,故不失为一种较好的临床筛查手段。  相似文献   
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